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men, in fact llie whole body, is shorter and stouter in the female, while the 

 genital armature is widely different. These - are sexual differences to be 

 found in all the families of moths. 



In the Phalaenids occur, as in some Bombycidce, namely, the species of 

 Orgt/ia, genera in which the females have only the rudiments of wings. 

 There are also other important differences, which we would draw attention to. 



The female Hybernia differs from the male in the body being much 

 shorter and thicker; in the scales being finer and shorter; in the simple 

 antennae and slightly stouter legs. The palpi are of nearly equal size in both 

 sexes, being remarkably short and hanging down. Denuding the head and 

 thorax, the head is considerably smaller in the female than the male, and tlie 

 eyes are less rounded. The front of the head is proportionately shorter and 

 broader, and less depressed between the eyes; the epicranium and clypeus 

 are a little fuller than in the male; the clypeus is shorter and broader than in 

 the male. 



But the most remarkable changes are seen in the female thorax, where 

 the entire tergum of the thorax is smaller than that of the first abdominal 

 segment. The female thorax of Hybernia is so much like that of Amso- 

 pterijr that I will reserve further descriptive remarks until the thorax of that 

 genus has been described. 



The head and body of the female Anisopteryx vernata differ from those 

 of the male, when undenuded, much as those of the female Hybernia from 

 the male. The differences in the head (pi. 7, fig. 26) are much greater in 

 Anisopteryx than in Hybernia, the head being wider. The head is smaller 

 and much wider in front, and the eyv^ much smaller in the female than in 

 the male In the female, the occiput is a transverse, narrow rim; the epi- 

 cranium is small, narrow, subtriangular ; while the clypeus is subscutellate, 

 as broad as long, with the front edge narrowing a little, and the margin invo- 

 lute; the surface is rather convex. The thoraces of the male and female of 

 A. pomctaria have been engraved. The thorax of the male (pi. 7, fig. 13, 13«) 

 is of the usual form, differing hut little from that of Eutrapeia. In the female 

 (pi. 7, fig. 14, 14a), however, the mesoscutum is about one-fourth as long as 

 wide, the hinder edge being slightly excavated ; the scutellum is very short 

 and wide, transversely narrow lozenge-shaped. The metathorax is remark- 

 ably short; the distance between the two halves, which are widely separated, 



